1. Field of the Invention
The present invention relates to a lens-fitted photo film unit and a method of producing the same. More particularly, the present invention relates to a lens-fitted photo film unit which includes an outer cover and in which a change in the appearance or addition of an auxiliary device can be effected easily at a low cost, and a method of producing the lens-fitted photo film unit.
2. Description Related to the Prior Art
A lens-fitted photo film unit is pre-loaded with unexposed photo film. In the lens-fitted photo film unit, a main body contains the photo film. A front cover is attached to the front of the main body. A rear cover is attached to the rear of the main body.
Various types of the lens-fitted photo film unit have been known recently. The number of designs of appearance of the lens-fitted photo film unit has been increased. For example, one type has an outer cover as a member separate from the front cover. To change the design of the lens-fitted photo film unit having the outer cover, the appearance can be changed by replacing the outer cover with a different one. The purposes of the outer cover are decoration and neatness of the appearance of the product. Thus, the outer cover is formed with a color distinct from that of the front cover. The shape of the outer cover can be determined with a particular feature. Also, JP-A 10-307324 discloses a lens adapter for a camera. The lens-fitted photo film unit or camera is provided with the lens adapter as an auxiliary device for an optically special purpose.
To change the appearance of the lens-fitted photo film unit of the type described above, it is necessary to redesign molds for the outer cover to modify its shape. Furthermore, a different type of resin is used and require changes in the process of the production. This causes a rise in the manufacturing cost. Also, the lens adapter of the above known type, for example for the purpose of a telephotographic effect, is secured to the housing of the lens-fitted photo film unit in a subsequent process in the manufacture. The addition of such a special structure to the lens-fitted photo film unit causes a rise in the manufacturing cost.
U.S. Pat. No. 5,784,652 (corresponding to JP-A 9-197622) and U.S. Pat. No. 5,988,893 (corresponding to JP-A 9-230460) disclose the lens-fitted photo film unit in which the outer cover is formed from transparent resin. An auxiliary sheet of paper is sandwiched between an inner face of the outer cover and a mechanism for taking an exposure. So the auxiliary sheet can be observed through the outer cover externally. However, there are shortcomings in this prior art in that the cutting and bending of the auxiliary sheet in the manufacturing process must be highly precise for the purpose of preventing interference with a shutter mechanism, a winder mechanism or the like. The manufacturing process is excessively difficult. Also, the number of steps in the assembly may be greater.
In view of the foregoing problems, an object of the present invention is to provide a lens-fitted photo film unit which includes an outer cover and in which a change in the appearance can be effected easily, and a method of producing the lens-fitted photo film unit.
Another object of the present invention is to provide a lens-fitted photo film unit which includes an outer cover and in which addition of an auxiliary device can be effected easily at a low cost, and a method of producing the lens-fitted photo film unit.
In order to achieve the above and other objects and advantages of this invention, a lens-fitted photo film unit comprises a main body pre-loaded with unexposed photo film. A front cover covers a front of the main body. An outer cover is secured to at least one portion of a front of the front cover. An auxiliary sheet is disposed between the front cover and the outer cover.
The outer cover is transparent to keep the auxiliary sheet observable externally.
The outer cover is formed from resin.
Furthermore, indicating information is recorded on the auxiliary sheet and observable through the outer cover.
The auxiliary sheet is formed from paper.
Furthermore, an opening is formed in the auxiliary sheet. A provisional retention projection is formed to project from the front cover or the outer cover, for being fitted in the opening, to retain the auxiliary sheet on the front cover or the outer cover before the outer cover is secured to the front cover.
The provisional retention projection has a size larger than a size of the opening, and is forcibly pressed into the opening.
Furthermore, a positioning projection is formed to project from a rear of the outer cover. A positioning through hole is formed in the auxiliary sheet, for receiving insertion of the positioning projection, to position the auxiliary sheet on the outer cover.
Furthermore, a taking lens is incorporated in the main body, for passing object light toward the photo film. The auxiliary sheet includes a central opening formed therein and disposed in front of the taking lens.
Furthermore, an anti-slip projection is formed to project from the front cover. A first through hole is formed in the auxiliary sheet, for receiving insertion of the anti-slip projection. A second through hole is formed in the outer cover, disposed in front of the first through hole, for receiving insertion of the anti-slip projection, the anti-slip projection being adapted for preventing a slip during holding.
Furthermore, a flash unit is incorporated in the main body, having a flash emitter for emitting flash light. A flash charger is incorporated in the main body, externally operable, for charging the flash unit. The auxiliary sheet includes a flash charger opening formed therein and disposed in front of the flash charger.
Furthermore, a viewfinder is incorporated in the main body, and adapted to observe a photographic object. The auxiliary sheet includes a viewfinder recess formed therein and disposed in front of the viewfinder.
Consequently, a change in the appearance can be effected easily, because of the use of the auxiliary sheet disposed between the front cover and the outer cover.
According to another aspect of the invention, a lens-fitted photo film unit is constituted by component part common use of a first lens-fitted photo film unit including a first main body pre-loaded with unexposed photo film, and a first outer cover for covering at least one portion of a front of the first main body. The lens-fitted photo film unit comprises a main body, constituted by the first main body, and pre-loaded with unexposed photo film. An auxiliary unit is secured to a front of the main body. An outer cover has a different shape from the first outer cover, and covers at least one portion of a front of the main body and the auxiliary unit.
The first outer cover and the outer cover are formed by use of a mold set including a main core mold and a main cavity mold opposed to each other. First and second inserts are selectively fitted on a predetermined one of the main core mold and the main cavity mold, the first and second inserts being adapted to form respectively the first outer cover and the outer cover.
The first lens-fitted photo film unit further includes a first front cover for covering a front of the first main body, and for receiving attachment of the first outer cover. Furthermore, a front cover covers a front of the main body, and for receiving attachment of the outer cover. The front cover has a different shape from the first front cover.
The first front cover and the front cover are formed by use of a second mold set including a second main core mold and a second main cavity mold opposed to each other. Third and fourth inserts are selectively fitted on a predetermined one of the second main core mold and the second main cavity mold, the third and fourth inserts being adapted to form respectively the first front cover and the front cover.
Furthermore, a flash unit is incorporated in the main body, has a flash emitter for emitting flash light. The auxiliary unit includes a flash charger, incorporated in the main body, externally operable, for charging the flash unit.
In one preferred embodiment, the front cover is constituted by the first front cover.
The main body includes a photographic light path for introducing object light to the photo film. The auxiliary unit includes a stop-down panel, having a stop-down opening, externally shiftable between an offset position and a set position, wherein the stop-down panel, when in the offset position, is set away from the photographic light path, and when in the set position, sets the stop-down opening in the photographic light path, to stop down the object light.
The outer cover further includes a sliding slot formed therethrough. The stop-down panel is secured inside the outer cover, and further includes a selector projection, formed to project toward a front, inserted in the sliding slot, for being slid by external operation.
According to still another aspect of the invention, a producing method of producing a lens-fitted photo film unit is provided. At first, a front cover is secured to a main body pre-loaded with unexposed photo film. A standard outer cover is provided. A specific outer cover on which a photographing auxiliary device is disposed is provided. In producing a normal lens-fitted photo film unit, said standard outer cover is secured to said front cover, and in producing a specific lens-fitted photo film unit, said specific outer cover is secured to said front cover.
Consequently, addition of an auxiliary device can be effected easily at a low cost, because of the selective forming of the two types of the outer covers by use of simple molding.